U.S. patent application number 13/027378 was filed with the patent office on 2012-08-16 for positioning tube of a vegetation cutter.
This patent application is currently assigned to YAO I FABRIC CO., LTD.. Invention is credited to TSUNG PEI YANG.
Application Number | 20120204427 13/027378 |
Document ID | / |
Family ID | 46635759 |
Filed Date | 2012-08-16 |
United States Patent
Application |
20120204427 |
Kind Code |
A1 |
YANG; TSUNG PEI |
August 16, 2012 |
POSITIONING TUBE OF A VEGETATION CUTTER
Abstract
A vegetation cutter includes a tubular casing and a power source
is connected to a first end of the casing so as to drive a drive
cable which extends through the casing. A cutting member is
connected to the drive cable and located on a second end of the
casing. A positioning tube is axially located in the casing and has
an annular sleeve through which the drive cable extends. The sleeve
has two ribs tangentially and diametrically connected thereto. The
two ribs are parallel to each other and extend in opposite
directions. The ribs contact an inner periphery of the casing. The
ribs are flexible and position the positioning tube in the casing,
and absorb vibration when in use.
Inventors: |
YANG; TSUNG PEI; (CHANGHUA,
TW) |
Assignee: |
YAO I FABRIC CO., LTD.
CHANGHUA
TW
|
Family ID: |
46635759 |
Appl. No.: |
13/027378 |
Filed: |
February 15, 2011 |
Current U.S.
Class: |
30/276 |
Current CPC
Class: |
A01D 34/905
20130101 |
Class at
Publication: |
30/276 |
International
Class: |
A01D 34/90 20060101
A01D034/90 |
Claims
1. A vegetation cutter comprising: a tubular casing; a power source
connected to a first end of the casing, a drive cable connected to
the power source and extending through the casing; a cutting member
connected to the drive cable and located on a second end of the
casing, the cutting member being rotated by the drive cable, and a
positioning tube axially located in the casing and having an
annular sleeve through which the drive cable extends, the sleeve
having two ribs tangentially and diametrically connected thereto,
the two ribs extending in opposite directions, the two ribs
contacting an inner periphery of the casing.
2. The vegetation cutter as claimed in claim 1, wherein the power
source is a motor or an engine.
3. The vegetation cutter as claimed in claim 1, wherein the cutting
member is a blade or a cutting line.
4. The vegetation cutter as claimed in claim 1, wherein the two
ribs are parallel to each other.
5. The vegetation cutter as claimed in claim 1, wherein the
positioning tube rotates in a first direction and the drive cable
rotates in a second direction which is in opposite to the first
direction.
6. The vegetation cutter as claimed in claim 1, wherein the
positioning tube is made of PA, PET, or TPEE.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a positioning tube for a
vegetation cutter, and more particularly, to a positioning tube
with two ribs which are flexible and extend in opposite directions,
the two ribs flexibly contacting the inside of the positioning
tube.
BACKGROUND OF THE INVENTION
[0002] A conventional vegetation cutter generally includes a
tubular casing with a power source and a cutting member connected
to two ends of the casing. A flexible drive cable extends through
the casing and is driven by the power source so as to rotate the
cutting member which cuts the plants. The cutting member can be a
blade or a cutting line.
[0003] A positioning tube is located in the casing and located
between the drive cable and the casing. Multiple ribs extend from
the positioning tube. When the power source is activated, the drive
cable generates vibration which can be absorbed by the positioning
tube and reduces friction between the drive cable and the
casing.
[0004] A conventional positioning tube is disclosed in U.S. Pat.
No. 6,739,058 and comprises a pipe portion with a inner pipe
portion received therein, three radial stay portions connected
between the inner pipe portion and the pipe portion. A drive shaft
extends through the inner pipe portion and is driven by a drive
source unit and a cutter blade is connected to the drive shaft. The
cutter blade is rotated when the drive source unit is activated.
The three radial stay portions are located at different spaces and
angles relative to each other. The inner pipe portion and the pipe
portion are integrally connected to each other.
[0005] Another conventional positioning tube is disclosed in U.S.
Pat. No. 4,953,294 and comprises a housing for accommodating the
motor therein; a protective tube which can be subjected to
vibrations during operational use of the tool, the protective tube
having a rearward end connected to said housing and having a
forward end, said tube also having an inner wall surface; a work
tool assembly mounted on said forward end; a drive shaft mounted in
said protective tube for connecting said motor to said work tool
assembly; a bearing sleeve unit arranged in said protective tube
and which can be subjected to radial pressure forces when mounted
in said tube; said bearing sleeve unit including an annular-like
center portion defining a bearing opening for holding and guiding
said drive shaft within said protective tube, said center portion
having an outer surface in spaced relationship to said inner wall
surface of said protective tube; said bearing sleeve unit further
including a plurality of supporting ribs extending outwardly from
said outer surface to brace said bearing sleeve unit against said
inner wall surface for supporting and centering said bearing sleeve
unit within said protective tube; and at least one of said ribs
being configured to extend approximately tangentially to said
annular-like center portion so as to be resilient in a direction
extending radially outwardly from said annular-like center portion
thereby substantially isolating said annular-like center portion
from said pressure forces and said protective tube from said
vibrations.
[0006] The first conventional positioning tube disclosed in U.S.
Pat. No. 6,739,058 includes three radial stay portions which are
complicated in shape and include the weight of the tool. The U.S.
Pat. No. 4,953,294 discloses multiple supporting ribs and one of
the ribs is resilient. Nevertheless, the multiple supporting ribs
are not convenient for assembling in the protective tube.
Furthermore, both of the two disclosures require precisely
machining and a small range of tolerance is allowed because of
their specific shapes. The sizes of the parts may change due to
change of temperature and the change of sizes might stock the
positioning tube in the casing. The precisely machined positioning
tube cannot be assembled quickly and easily.
[0007] The present invention relates to a vegetation cutter and
comprises a tubular casing with a power source and a cutting member
connected to two ends thereof. A drive cable extends through the
casing and is connected to the power source. The cutting member is
connected to and driven by the drive cable. A positioning tube is
axially located in the casing and has an annular sleeve through
which the drive cable extends. The sleeve has two ribs tangentially
and diametrically connected thereto, and the two ribs extend in
opposite directions. The two ribs contact an inner periphery of the
casing. The ribs are flexible so that the positioning tube is
easily positioned in the casing by deforming the ribs. The
positioning tube has a simple structure and is light in weight.
[0008] The primary object of the present invention is to provide a
positioning tube with an annular sleeve so that the drive cable
extends through the annular sleeve. The sleeve has two flexible
ribs connected thereto and the two ribs extend in opposite
directions and contact an inner periphery of the casing. The ribs
are flexible so that the positioning tube is easily positioned in
the casing by deforming the ribs.
[0009] Another object of the present invention is to provide a
positioning tube which includes an annular sleeve and two ribs. The
positioning tube is easily manufactured and light in weight. The
positioning tube can be made by resilient material.
[0010] Yet another object of the present invention is to provide a
positioning tube with two ribs which extend in opposite directions
and are in contact with the inner periphery of the casing. The
positioning tube can be made with larger range of tolerance and
less cost.
[0011] By the two flexible ribs on the positioning tube, the change
of temperature does not affect the snug contact between the ribs
and the inner periphery of the casing.
[0012] The present invention will become more obvious from the
following description when taken in connection with the
accompanying drawings which show, for purposes of illustration
only, a preferred embodiment in accordance with the present
invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a perspective view to show the vegetation cutter
with the positioning tube of the present invention received
therein;
[0014] FIG. 2 is a cross sectional view taken along line 2-2 in
FIG. 1;
[0015] FIG. 3 is a perspective view to show the positioning tube of
the present invention, and
[0016] FIG. 4 shows that the rotational directions of the drive
cable and the positioning tube are opposite to each other.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0017] Referring to FIGS. 1 to 4, the vegetation cutter generally
comprises a tubular casing 10, power source 11 connected to the
first end of the casing 10, a cutting member 13 connected to the
second end of the casing 10, and a positioning tube of the present
invention received in the casing 10.
[0018] The power source 11 is a motor or an engine, and a drive
cable 12 is connected to the power source 11 and driven by the
power source 11. The drive cable 12 extends through the casing 10
and is made of metal and includes proper flexible and pre-set
torque.
[0019] The cutting member 13 is connected to the drive cable 12 and
rotated by the drive cable 12. The cutting member 13 is a blade or
a cutting line.
[0020] The positioning tube 20 is axially located in the casing 10
and has an annular sleeve 21 through which the drive cable 12
rotatably extends. The sleeve 21 has two ribs 22 tangentially and
diametrically connected thereto, and the two rib portions 22 are
parallel to each other. Furthermore, the two ribs 22 extend in two
opposite directions. The two ribs 22 contact the inner periphery
101 of the casing 10. The two ribs 22 are flexible and can be bent
toward the center of the sleeve 21. By the flexibility, the
positioning tube 20 can be easily installed in the casing 10. When
the positioning tube 20 is installed in the casing 10, the ribs 22
are released and bounce back to contact the inner periphery 101 of
the casing 10. There are two contact points between the positioning
tube 20 and the casing 10 to well position the positioning tube 20.
By the flexibility of the ribs 22, the positioning tube 20 can also
be easily removed from the casing 10. The positioning tube 20
absorbs vibration from the casing 10. In order to avoid that the
positioning tube 20 and the drive cable 12 to be co-rotated in the
same direction, the positioning tube 20 rotates in a first
direction and the drive cable 12 rotates in a second direction
which is in opposite to the first direction as shown in FIG. 4 so
as to keep the ribs 22 contacting the inner periphery 101 of the
casing 10. The positioning tube 20 is made of PA, PET, or TPEE
which is light in weight.
[0021] The positioning tube 20 is made by resilient material such
as rubber and the ribs 22 and the sleeve 21 can be integrally
manufactured. Because the ribs 22 can be deformed, the positioning
tube 20 does not need to be manufactured to have high precision
standard. The range of tolerance can be larger which reduces the
manufacturing cost and the size change due to temperature does not
affect the contact between the ribs 22 and the casing 10.
[0022] Because there are two ribs 22 extending from the sleeve 21,
so that when installing the positioning tube 20 in the casing 10,
one rib 22 can be bent toward the sleeve 21 to have more space to
allow the positioning tube 20 to be inserted into the casing 10.
The rib 22 can bounce back to contact the inner periphery 101 of
the casing 10 when the positioning tube 20 is set in the casing 10.
There are only two ribs 22 on the sleeve 21 so that the
manufacturing cost can be lowered.
[0023] While we have shown and described the embodiment in
accordance with the present invention, it should be clear to those
skilled in the art that further embodiments may be made without
departing from the scope of the present invention.
* * * * *